1. Field of the Invention
The present invention relates to a operator enclosure for an agricultural tractor and specifically to an enclosure having a rollover protective structure (ROPS) with a front upper cross member that is raised relative to the left and right side upper members to improve operator visibility when using a front-end loader.
2. Description of the Related Art
Many modern agricultural tractors have an operator station with a flat floor forward of the operator's seat. This provides greater ease of ingress and egress and improved operator comfort compared to many older designs in which the floor has a raised center portion with lowered foot rests on each side of the raised center portion. To provide the flat floor, the operator station is raised to a higher position relative to the tractor frame than in earlier designs. This results in an overall increase in the height of an operator enclosure, i.e. cab. However, it is generally desired to keep the overall height of the tractor as low as possible, to maximize clearance when entering a building.
Also important in the design of the operator enclosure is the operator visibility. When the tractor is equipped with a front-end loader, it is also important to have upward visibility to view the loader bucket in a raised position. While upward visibility can be improved by raising the height of the enclosure roof, there are practical limits to the height of the tractor as mentioned above. One solution to provide greater upward visibility for a raised loader bucket, without increasing the roof height, is to add a viewing window in the roof of the enclosure. While a viewing window enables the bucket to be seen in a raised position, as the loader bucket is being raised, it must pass through a region where visibility is blocked by the front upper cross member of the enclosure frame. Furthermore, the addition of a viewing window in the roof can decrease the packaging space in the roof area for ventilation ducts, radios, etc. and add significant cost to the tractor.